Safety locking device.



C. F. ALBRECHT.

SAFETY LOCKING DEVICE.

APPLICATION FILED APILZO, 1914.

1,1 17,750. Patented Nov. 17, 1914.

THE MORRIS PETaES 0:.. PHOTOLITNQ.. WASHING roN, D. C.

UNVFED STATES PATENT CFFCE.

CHARLES E. ALBRECHT, OF CLEVELAND, OHIO, ASSIGNOR 0F TEVO-FIFTHS TO BION D. FORD, 0F CLEVELAND, OHIO.

SAFETY LOCKING DEVICE.

Application led April 20, 1914.

To all Iwhom it may concern:

Be it known that I, CHARLES F. ALBRECHT, a citizen of the United States, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Safety Locking Devices, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings.

This invention relates to safety locking devices, and more particularly to devices of this character which are adapted for use with tools operated by Huid pressure, such as pneumatic hammers, drills, and air-operated rotary pistons. The particular embodiment of my invention disclosed herein is shown as applied to a pneumatic hammer and is arranged so that it will prevent the accidental displacement of the air-controlling valve in the handle, as by the unintentional impact of the trigger against the hand of the operator or against any other object. As is well known to those who are skilled in this art, accidents attended with more of less serious results have resulted from the unintentional displacement of the valve in tools of the kind referred to, whereby the pressure fluid is admitted to the tool and the tool placed in operation at an inopportune time or in an inopportune place.

lt is the general object of this invention to provide means whereby such unintentional operation in tools of this character may be prevented.

A further object of the invention is to secure this result in and through a particularly simple, economical, and eiiicient construction, which can be readily attached to and removed from tools of the character referred to with no material change in, or addition to. such tools.

I accomplish the foregoing and other objects, which may appear hereinafter, in and through the construction illustrated in the drawings forming part hereof, wherein- Figure 1 represents a side elevation of the handle end of a tool of the pneumatic hammer type, a part of the handle and the cooperating parts being shown in section, the valve being locked in closed position in Specification of Letters Patent.

S, the ports l Patented Nov. 17, 1914.

serial No. 833,008.

and through my attachment; Fig. 2 is a sectional detail of the handle, showing the parts of my locking device or attachment when released to permit the operation of the valve in the ordinary manner; Fig. 3

a perspective view ot' my locking device or attachment; and Fig. 4 a sectional view through the locking device corresponding to the line 4 4 of Fig. l.

Describing the various parts illustrated herein by reference characters, l denotes the cylinder and 2 the handle of a tool of the pneumatic hammer type. The tool shown herein is of standard construction and contains the passageway 3 through .vhich pressure iiuid is supplied to the cylinder 1 by means of a connection 4 which is adapted to receive the ordinary hose (not shown). The portion 2a of the handle which is grasped by the operator is provided with a bore 5 which intersects the passageway 3, and within this bore there is inserted a sleeve or bushing 6 having two sets of ports 7 and 7 communicating with the connection passageway 4a and the ports S communicating with the passageway 3, the sets of ports being separated by an annular wall 9 which fits within and fills the bore 5.

For convenience of description, it will be assumed that the tool is operated in a vertical position, as shown in Fig. 1, and the terms right and left and top and bottom will be employed in accordance with this assumption The upper left hand end of the handle part 2a is provided with a. slot 10 through the upper part of which there extends :l pin 11, to which the trigger 12 is pivoted. The upper part of the sleeve or bushing 6 may be cut away or slotted, as shown at 6, to receive therewithin the valve-operating lug 13 of the trigger, the handle 14 of the trigger projecting outside of the slot 10, in position for convenient operation.

Reciprocably mounted within the sleeve or bushing 6 is a valve, indicated generally at 15. This valve is provided with two cylindrical abutments 16 and 17, the abutment 16 being at the right hand end of the valve and the abutment 17 being spaced a suiicient distance from the abutment 16 to provide, with the reduced connecting stem l52L and the inclosing bushing or sleeve 6, an annular passageway 1S which extends between and connects the ports 5 and 7 when the valve is moved to the right by the trigger l-l- -in a manner well known to those famili with this art. A spiral spring 19 which s within the right hand portion of the `leere or bushing G bears at one end against abutment 15 registering with the ports .7 rige-.inst a block 20 which is threaded i-nto lie outer or right hand end of the sleeve or ,gushing and tends to hold the valve in the position shown in F ig. 1, namely; with the abutment 16 registering with the ports 7 and cutting el? tl e supply of pressure fluid to the passageway 3, the end of the valve which is opposite the abutment 16 bearing against the lug 13.

The parts hereinbefore described and identiiied by the numerals 1 to 19 inclusive are of standard construction.

The bloclr 2O constitutes a part of the device or attachment which l employ for locking the valve 15 against displac aient through an accidental operation or" the trig- The bloclr projects outwardly beyond the sleeve or bushing 6 and is provided with a cylindrical abutment 21. Near its outer end the abutment 21 is bored transversely, as shown at 22. The block 2O of which the abutment 21 forms a part is provided with a central longitudinal bore for the reception oi" a hollow rod or tube 23 which is adapted to engage the adjacent end or" the valve 16 and positively lock the valve lin its cutot't' position with reference to the ports 7, under circumstances to be described hereinafter.

a denotes an external sleeve which surrounds the abutment 21 and is provided with a bayonet slot 25, 26, the transverse portion 26 of the slot being located at the right is adapted to receive therewithin a pin 27 which may be driven into the upper portion of the bore 22 and which pin is preferably of such length that its lower end will abut against the hollow rod or'tube 23. The outer or right hand end of the sleeve is closed by a head 24a to which the outer or right hand end of the hollow rod or tube is secured, and the spiral spring 28 surrounds the outer end of `this rod or tube and at one end against the abutment 21 and at its opposite end against kthe head tend ng to move the sleeve 24 and the attached tube or rod 23 outwardly and away from the valve 15. For convenience et manipulation, the outer end of the sleeve is lrnurled, as indicated at 2th. By boring entirelyl through the abutment 21, the pin 2'? may be easily ba'clred out through the end or outer end thereof. This slot` said bore, the holes 23a in the tube or rod, and the hole 24C in the lower portion of the sleeve.

F rom the foregoing it is believed that the operation will be apparent. When the operator finishes the particular work on which he is employed, he grasps the sleeve 2Liyby the knurled or milled end thereof, pushes the sleeve and the attached tube or rod 23 inwardly until the pin 27 reaches the lateral portion 26 oi the bayonetslot, whereupon he gir/'es the sleeve a turn to the right, bringing the pin V27 into the lateral portion 'of the slot, thereby locking the parts in the position shown in F ig. 1. ln this position, it will be evident that thel valve abutment 16 will completely cut eti' the flow of pressure iuid .trom the passageway 3 and that thevalve cannot be operated by pushing the trigger handle 1i inwardly, or to the right, either by accident or by design. ln other words, the .operating movement of the trigger as well as the movement of the valve is completely blocked. 1When, however, it is desired to operate the tool, it is necessary only to turn the sleeve 24: a suiiicient distance to the left to bring the pin 27 into the longitudinal portion 25 oit' the bayonet slot, whereupon the spring 28 will ,throw said sleeve and the attached hollow rod or tube 23 to the right, as shown in'ltig. 2. The valve then may be operated in the usual manner by the trigger. n

The blocking device 23 is bored or tubular to facilitate the opening of the valve by the trigger. Furthermore, a pin 23h is carried by the device 23 to prevent the sameA from being forced out of the block 21 should the pin 27 happen to break or fall out.

From the foregoing it will be evident that I have produced a locking `device fortools of the character set -`torth which is extremely simple of construction and eliicient in operation and one which can be applied to existing standard tools `with no alteration thereof and with the mere addition of a small, simple and economical attachment thereto.

Having thus described my invention, what l claim is 1. A fluid pressure operated tool comprising. in combination, a barrel or cylinder, a handle for said barrel or cylinder provided with -a passageway for pressure iuid, a valve in said handle adapted to control the iiow of fluid through such passageway, a trigger carriedby the handle for operating the valve., a deviceadapted to engage the valve and'block it against movement by the trigger. means for retaining said device in blocking position, and a spring arranged to move said device out ol valve-blocking .position when the said device is released.

2; A vfluid pressure operated tool vcomprising, in combination, a cylinder or barrel, there being a passageway for conducting pressure fluid to said cylinder or barrel, a valve movable transversely with respect to said passageway to control the flow of fluid therethrough, a manually operated device for unseating said valve, a device adapted to engage said valve and prevent the unseating thereof, means for locking the last mentioned device in valve-engaging position, and means for automatically moving the last mentioned device out of valve-engaging position.

3. A liuid pressure operated tool comprising, in combination, a barrel or cylinder, a handle therefor, said handle having a passageway for conducting pressure fluid to the barrel or cylinder, a valve in said handle controlling said passageway and normally preventing the passage of fluid therethrough, a trigger carried by said handle and adapted to nieve the valve in a direction to permit the flow of fluid through the passage, a locking device for said valve, said device comprising a member which is adapte.l to engage the end of the valve opposite said trigger', means for locking said member in valve engaging position, and a spring tending to move said member out of valveengaging position.

e. A fluid pressure operated tool comprising, in combination, a barrel or cylinder, a handle therefor provided with a passageway for supplying pressure fluid to the cylinder or barrel, a bushing extending across said passageway and provided with one or more ports for admitting pressure fluid to the passageway, a valve in said bushing, a trigger carried by the handle and having a portion adapted to engage the valve to move it in a direction to permit the flow of fluid through said port or ports, a locking device for preventing the movement of the valve by the trigger, said device comprising a body which is carried by the end of Vthe bushing opposite the trigger, a valve-engaging member slidably mounted in said body, a spring tending to move said member away from the valve, and means for locking said member in valveengaging position against the action of said spring.

5. A fluid pressure operated tool comprising, in combination, a cylinder or barrel, a handle therefor lirovided with a passageway, a bushing intersecting said passageway and provided with one or more ports through which pressure fluid is adapted to enter the passageway, a valve reciprocably mounted within the bushing and controlling said port or ports, a trigger carried by said handle and having a portion adapted to engage the valve and operate it in a direction to permit the flo-w of fluid through said port or ports, said trigger being located adjacent to one end of said bushing, a locking device carried by the opposite end of the bushing, said device comprising a body threaded into the bushing and provided with a longitudinal bore, a valve engaging member slidably mounted in said bore and adapted to engage the adjacent end of the valve, a sleeve having a head to which the outer end of the hollow rod or tube is secured, a spring interposed between said head and said body and surrounding the valve -engaging member, and a pin carried by said body, the sleeve being provided with a bayonet slot coperating with said pin to retain the valve-engaging member in its inwardly adjusted position against the action of said spring.

G. A fluid pressure operated tool comprising, in combination, a cylinder or barrel, said tool being provided with a passageway and with a bore intersecting said passage-v way, a valve reciprocably mounted within the bore and controlling the passageway, means whereby said valve may be operated in a direction to permit the flow of fluid into said passageway, a locking device slidable within said bore and adapted to engage the adjacent end of the valve, means for locking said device in such valve-engaging position, and a spring for moving said device out of valve-engaging position.

7. A fluid pressure operated tool comprising, in combination, a cylinder or barrel, said tool being provided with a passageway and with a bore intersecting said passageway, a valve reciprocably mounted within the bore and controlling the passageway, means whereby said valve may be operated in a direction to permit the flow of fluid into said passageway, a locking device slidable within said bore and adapted to engage the adjacent end of the valve, a pin and bayonetslot connection between the locking device and the tool for retaining the said device in valve-engaging position, and a spring for moving said device away 'from said valve.

S. In a fluid pressure operated tool having a bore for fluid under pressure, a valve reciprocably mounted within the bore and controlling the flow of fluid therethrough, means whereby said valve may be operated longitudinally of said bore in one direction to permit the flow of fluid therethrough, a locking device which is slidably mounted within said bore and is adapted to engage the valve to prevent the movement of the same in a direction to permit the flow of fluid therebeyond, means for locking said device in such valve engaging position, and a spring `for moving said device out of' valve engaging position.

9. A fluid pressure operated tool having a passageway for pressure Huid, a valve controlling the flow of fluid through said passageway and movable in one direction to permit the flow of Huid through such p sdevice to 'move it out of Valve blocking posi- 10 sage-Way, means for operating the, valve 1n tion.

such direction, a blocking device movable in In testimony whereof, hereunto my thesame linear direction as the Valve and signature in the presence of tWo Witnesses. adapted te engage the Valve to prevent its ,1 movement in a direction to permit the flow CHARLES F ALBRLCHT of uid through the passageway, means for llitnesses: locking said device in such Valve blocking J. B. HULL,

position, and a spring coperating With said BIoN D. FORD.

Copies of this patent may be obtained for ve cents each, by addressing the commissioner of Eatents, Washington, D. C. 

